Is this passive play correct?

[captain_swing]

I'm not the hero in this post but thought it was an interesting hand--at first it seems way too passive but maybe it's not so bad. I just sat down so no reads.

Party 3/6
Hero is MP3 with AcKh
Pre flop
UTG calls, hero calls, BB calls.

Flop 3.33 SBs
Kc Jd 6s
Utg bets, hero calls, BB folds.

Turn 5.33 SBs
Jh
Utg bets, hero calls.

River 4.67 BBs
Jc
Utg bets, hero calls.

Not raising preflop is obviously wrong but what about the other streets?